A security consultant believes a blogger's detention in China this week is retaliation against countries that have rejected - or are considering rejecting - the 5G rollout by the tech company Huawei. The prominent writer and former diplomat Yang Hengjun, an Australian citizen, is the latest person to be locked up in China in what analysts believe is a government strategy to get even with the West. As well as the detention of Yang Hengjun a few days ago, two Canadian citizens have been detained in China in recent weeks. Huawei has been banned from mobile phone projects in New Zealand, the United States, Canada, the United Kingdom and Germany amid fears the latest 5G technology could be used by the Chinese government for spying. Security consultant Paul Buchanan told reporter Matthew Theunissen that any New Zealander doing business in China is potentially at risk.